Nitrate and nitrite

Lihue-Kapaa

Nitrate and nitrite enter water from fertilizer runoff, septic tanks and urban runoff. These contaminants can cause oxygen deprivation for infants and increase the risk of cancer. Nitrite is significantly more toxic than nitrate. Click here to read more about nitrate.

MORE ABOUT THIS CONTAMINANT

Samples

Samples exceeding legal limit (MCL)

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Detections	Range of results
2014	N/A	0	0	N/A
2015	N/A	0	0	N/A
2016	0.504 ppm	18	13	ND - 1.80 ppm
2017	0.425 ppm	16	10	ND - 1.000 ppm
2018	N/A	0	0	N/A
2019	N/A	0	0	N/A

ppm = parts per million

State and national drinking water standards and health guidelines

EWG Health Guideline 0.14 ppm

The health guideline of 0.14 parts per million, or ppm, for nitrate and nitrite is based on the equivalent health guideline for nitrate, as defined in a peer-reviewed scientific study by EWG. This guideline represents a one-in-one-million annual cancer risk level.

EPA Maximum Contaminant
Level (MCL) 10 ppm

ppm = parts per million

All test results

Date	Lab ID	Result
2016-03-07		ND
2016-03-07		0.770 ppm
2016-03-07		0.980 ppm
2016-03-07		1.20 ppm
2016-03-09		ND
2016-03-09		ND
2016-03-09		0.460 ppm
2016-03-09		ND
2016-03-21		0.310 ppm
2016-03-21		0.560 ppm
2016-03-21		0.430 ppm
2016-03-21		0.310 ppm
2016-03-22		1.80 ppm
2016-03-22		0.380 ppm
2016-03-22		ND
2016-04-04		0.520 ppm
2016-04-04		0.500 ppm
2016-04-04		0.850 ppm
2017-01-23		0.820 ppm
2017-01-23		ND
2017-01-23		ND
2017-01-23		ND
2017-01-23		ND
2017-01-25		0.990 ppm
2017-01-25		0.460 ppm
2017-01-25		1.000 ppm
2017-02-13		ND
2017-02-13		0.390 ppm
2017-02-13		ND
2017-02-15		0.500 ppm
2017-02-15		0.710 ppm
2017-02-15		0.520 ppm
2017-02-15		0.620 ppm
2017-02-15		0.790 ppm